This invention relates to autonomous water vehicles.
As a wave travels along the surface of water, it produces vertical motion, but no net horizontal motion, of water. The amplitude of the vertical motion decreases with depth; at a depth of about half the wave length, there is little vertical motion. The speed of currents induced by wind also decreases sharply with depth. A number of proposals have been made to utilize wave power to provide useful results. Reference may be made, for example, to the patents and applications incorporated by reference above, and to U.S. Pat. Nos. 986,627, 1,315,267, 2,520,804, 3,312,186, 3,453,981, 3,508,516, 3,845,733, 3,872,819, 3,928,967, 4,332,571, 4,371,347, 4,389,843, 4,598,547, 4,684,350, 4,842,560, 4,968,273, 5,084,630, 5,577,942, 6,099,368 and 6,561,856, U.S. Publication Nos. 2003/0220027 and 2004/0102107, WO 94/10029 and WO 87/04401. The entire disclosure of each of those patents, patent applications and publications is incorporated herein by reference for all purposes.
Liquid Robotics, Inc. has developed particularly useful water vehicles (“Wave Gliders”®), as described for example in U.S. Pat. Nos. 7,641,524 and 8,043,133, which are autonomous (i.e. which do not carry a human being) and which can traverse the oceans for long periods of time under the direction of signals sent to the vehicle from a control location, while gathering useful information which can be communicated to a reception location and/or recorded.